


Yami from Taicho to Baby

by nfarious



Category: Black Clover - Tabata Yuki (Anime & Manga)
Genre: Aged-Up Character(s), Diapers, Inspired by Roleplay/Roleplay Adaptation, M/M
Language: English
Status: Completed
Published: 2021-02-07
Updated: 2021-02-07
Packaged: 2021-03-12 19:21:06
Rating: Mature
Warnings: Graphic Depictions Of Violence
Chapters: 8
Words: 3,370
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29265687
Author URL: https://archiveofourown.org/users/nfarious/pseuds/nfarious
Summary: Yami has been avoiding dueling with Asta not cause he was scared of the brat but lately his stomach has been acting up.Asta however wont take no for an answer and he is set on breaking his limits. But as Asta breaks limits Yami finds himself losing not only his title but so much more.Big changes are in store for the Black Bulls.
Relationships: Asta & Yami Sukehiro
Kudos: 5





	1. Chapter 1

**Author's Note:**

> I do not own Black Clover or the characters in it, all rights go to the Yuki Tabata.
> 
> This is for entertainment purposes only

Ever since the Clover Kingdom well mainly Yuno, Yami and him stopped the eye of the Midnight Sun and more importantly that devil Asta noticed Yami was absent more often always running off. He thought it strange but let it go for the time being. 

Asta knew Yuno was constanly growing stronger and he knew he had to keep up. He asked Yami to spar with him but Yami told him later. And then finally Yami had tasked Asta with proving himself if he wanted a duel with him. If Asta wanted to fight Yami he would have to first best the team of Magna and Luck. 

Asta accepted the challenge. But the task wasnt easy. Magna used his magic to make his fire balls invisible and Lucks movements were so eratic Asta couldnt keep up. The pair ran Asta ragged. Asta decided to focus harder. He began to focus not on their magic but reading their ki. Asta smashes his sword into Magnas fire ball and knocks it back into Luck. Asta didnt let up and he slams the pair with the blunt edge of his antimagic sword. 

Asta had earned his right to challenge Yami. He was estatic but his excitement was brought down as Yami gave him more tasks. It was feed the beasts then clean the base. Then get him some toilet paper and then baclk to feeding the beasts. Asta was beginning to wonder why Yami wasnt dueling him.

Asta was gonna get to the bottom of this. Asta was gonna do something drastic he was gonna open Yami's private office ie. Yami's restroom.


	2. Chapter 2

Yami was in his restroom. Lately his stomach hasnt been agreeing with him much. Yami spent most of his time in his trhone room as some Black Bulls call it.   
Yami sighs as he rubs his stomach taking a drag of his cigarette. "Man stupid stomach aches. What the hell did i eat?" Yami wonders as he takes another drag of his cigarette as he tries to use the restroom yet again. 

Taicho Taicho!" Asta calls out as he bangs on the restroom door. "Taicho come on spar withe me!" Asta calls out more. 

"Oi Oi brat cant a man take a dump in peace!" Yami yells. "Taicho come on!" Asta bangs on the door.   
Yami was growing more agitated. "Brat im trying to take a shit!" 

"Okay Yami Taicho but after spar with me I beat Luck and Magna and i fed the beasts and cleaned the base from top to botrom!" Asta says. 

"Brat you are years away from breaking your limits to fight me!" Yami says as he doesnt hear Asta or that incessant knocking. Yami trys to relax again only for Asta to yell "Taicho I need to break my limits or Yuno will leave me in the dust!"


	3. Chapter 3

Asta was persistant he banged on the door. "Taicho come on I cant let Yuno get ahead of me!" "Brat Im busy!" Yami grumbles getting more and more irrtated. 

Yami had enough of Astas knocking and he smashes his hand through the door to grab Astas head. "Nice try taicho but I read your Ki!" Asta says. 

"You want a match fine brat but once i lay you out remember you asked fot it!" "Yes Taicho! Im so excited!" Asta says with a smile. 

Yami cracks his neck and he motions Atsa to come at him. Asta doesnt underestimate his Taicho and he powers up and goes into his antmagic form. 

Yami smirks. "Youve gotten stronger brat but not good enough!" Yami says as he sees Asta charge at him head on. Yami goes to kick Asta but was surpsied when Asta pulls back at the last mintue to grab his leg to throw him off balance. 

Yami easily recovers and he fires off a darkless slash. Asta slashes at Yamis attack but the overwhelming mana pushes Asta back. Asta manages to deflect the blast. "Hows that Yami tai...cho!" Asta was gonna celebrate but he saw several more darkness slashes coming his way. 

Asta tries his best to block them cause they would destroy the base. But he gets blown back and out the base into the nearby woods. 

Damn brat you see you arent ready now dont bug me again while im trying to use the restroom!" Yami huffs as he lights a new cigarette but he feels a heavy darkness. 

Asta was in the woods groaning. Asta was spent but he hears it. The devil inside him. "I refuse to let you hold me back anymore! I'll fight him myself!" "No you wont im gonna break my limits now lend me your power. 

Yami smokes but he spots Asta emerging from the woods. "Give it up Brat i admire your spirit but you argh!" Yami had to draw his katana to defend as Asta blitzes him with a speedy strike. "Oi oi seems you have some fifhght in you bur it ends brat im breakig my limits!" 

Yami goes to atrack with a lighless slash to end the match but he grunts in pain as Astas hilt slams into his gut. Yami taicho?" Asta powers down in stunned silence. "What brat?" But Yami then feels it he was pissing himself. But it gets much worse as he has a messy accident in his pants.


	4. Chapter 4

Asta was for once silent. He couldn't believe his eyes. But there he was starring at a wet spot in his captains trousers. 

Sure the dark color of Yami's pants hid most of the accident they did little to hide the mess in his backside. 

Yami had actually dropped his cigarette as he too was silent. Yami couldn't fathom how he not only pissed himself but he had soiled himself to boot. 

Finally the silence was broken with Asta asking "Yami taicho are you alight?" 

"Training is over get out now!" Yami says as Asta's inquiry had snapped him out of his dazed stupor.. Yami had to get cleaned up it was bad enough the brat saw such a humialting act. 

Asta didn't move he recalled what the sister said when he grew up in the village. Big boys don't soiled themselves or wet the bed. Those that do need extra protection. 

"Oi what are you still doing here brat I said training is over leave now before I show you my broken limits!" Yami says sternly.

Taicho! Go shower ill take care of everything!" Asta says as he rushes out to find Magna or Finral as he needed a lift to his home village. He knew if anyone could help it would be the Sister. 

Yami didn't know what Asta meant by fix everything but he could care less. He dragged his feet and made it to his bathhouse. He discarded his soiled garments and cleaned himself up some before drawing a warm bath. The only good thing was it seemed he wasn't constipated anymore.

Asta managed to find Finral and he asks for his help. "Finral senpai I need to get to my village now come on!" 

"No way Asta I'm your senior and I am not some personal taxi service!" Finral says crossing his arms in annoyance.

"Come on please!" Asta asks again. "The answer is no Asta!" Finral says. Asta was starting to think he should ask Magna but then it hits him. "Finral senpai there is like alot of ladies at my village." Asta says with a smile. 

"What yeah right I've been there already Asta there isn't any ladies but that mean sister that attacked me with a fist of water!" Finral huffs.

"Senpai you didn't look last time we had elves to stop. Trust me." Asta says. "Hmm alright but only for the ladies lets go!" Finral says his eyes lighting up like stars at the idea of village girls he could sway and swoon being a magic knight.

Asta thanks Finral as he knew he had to help his Taicho out. 

Yami was enjoying the quiet as he soaked in the bath. He lights another cigarette. The blow from Astas blade seemed to have helped his stomach problems as Yami didn't feel as bloated.

Finral looks for the ladies but all he gets is a huge fist of water being slammed into him.

"I'm gonna dry off stupid Asta stupid village! I'm a magic knight you know!" Finral huffs as he goes to wring out his uniform. 

Once Finral was occupied with getting dry Asta asks the sister for help. 

"Asta what can I help you with your a magic knight now?" The sister asks wondering what Asta could possibly need. After all she witnessed him and Yuno fighting off elves and saving Father.

"Sister remember when I was little and I blamed yuno for my bed?" Asta says not wanting to say it. 

"You mean your bedwetting what about are you having accidents again Asta?" She asks giving him a quizzical look.

"What no Sister I'm dry. But I have someone who isn't just wetting the bed at night but wide awake and he well he." Asta whispers to the Sister about the messy accident.

"Oh my that isn't good. Alright I'll see what I can do." Sister says. Finral meanwhile was being grilled by the orphans. It was rare for them to see magic Knights since Yuno became Vice captain of the Golden dawn and Asta had been training like mad and busy with odd missions for the Black bulls.

Thanks sister." Asta says as he waits for her. Sister returns with a full knapsack. "Now I trust you know how to change one or do you need a reminder?" Sister asks Asta. 

"I got it Sister! Thanks again. And I promise I'll send more letters home." Asta says with a smile.


	5. Chapter 5

Asta tells Finral he was ready to head back. "Again Asta I'm not a taxi service and girls huh last time I trust you!" Finral says as he opens a portal to the black bulls base.

Finral goes to see if Vanessa will share some of her booze after his day he needed a drink. 

Asta meanwhile heads to Yamis room. He begins to lay everything out just like Sister use to do while he and Yuno were in the bath back at the orphanage.

Yami takes a long drag of his cigarette. The warm water felt good on his stiff muscles. Yami was relieved it was Asta that saw him as the brat was strong but he wasn't too bright so Yami didn't think he had to worry about Asta running his mouth off about his well anyway he thought no sense dwelling on it.

Asta laid out the changing mat. Sister had it made by a friend who used rubber magic. So it made changes easy and less messy for the bed.

Asta sees the cloth diapers. He remembered these course they were smaller then but Asta had told sister a little fib that the baby was big for his age. Then again it wasn't really a lie was it?" Asta thinks to himself after all big boys and certainly men don't piss themselves and they defiantly don't go number two in their pants. Even Asta when he had his problem didn't mess himself.

Yami was finishing up his bath. He had needed that. He wraps the towel around his waist and heads for his room.

"Oi brat the hell you doing in here?" Yami asks surprised as he sees Asta in his room.

"Hi Yami Taicho sorry I'm late sister had to adjust them for you." Asta says. "Adjust them what the hell are you talking about brat get out of my room now!" Yami was getting pissed.

"Taicho relax I told you I'm gonna take care of everything. Now then lay down." Asta says.

"Get out!" Yami grabs Asta by his head and tosses him out his room. Yami just wanted to be alone but then he sees it. First the bright baby blue mat. It was weird sure but then it made more sense as Yami spots the cloth diaper on his bed.

Yami slashes the cloth diaper with his katana. The brat had a lot of nerve. Yami dries off. He tosses the towel to the floor and looks for his fundoshi.

Yami slips it on and he gets a fresh pair or pants on. He goes to get his shirt on.

Asta sighs he hopes his Taicho wears the protection. But he can't force it he just wanted to help.

Yami dresses and he decides he needs time to himself so he stays in his room. Today was gonna make him seriously smoke the whole pack at once. He thinks to himself.

Asta heads to his room. He couldn't get over the fact his Taicho not only wet himself but he went number two to. No one did that Asta thought.

Asta was so lost in his thoughts he soon dozes off. Asta normally dreams of being the Wizard king but that wasn't the dream today. Asta was facing the shadowy silhouette of the demon inside him.

"What do you want?" Asta asks annoyed that he wasn't the wizard king. He loved that dream. 

What do I want isn't important. Asta you're a failure!" The demon says. "What I am not!" Asta yells back angrily. 

"Oh you aren't huh well your Taicho soiled himself like a child and you don't even get him properly dressed. If he goes out and soils himself in public it's all your fault. Imagine it the captain of the black bulls soiling himself they will never let anyone from the black bulls be Wizard King!" 

"They will to I mean they hey just Yami Taicho messes not us!" Asta yells back. "Really you think so maybe if it was you or another member but he's the captain your whole guild will be made a laughing stock and you're dream will always be that a dream!" The devil says.

Asta sat up in his bed in a cold sweat. It was just a bad dream right. Yami Taicho wouldn't mess himself again. But what if he does. Men don't mess themselves they dont." Asta thinks as he recalls Sisters words growing up. Asta debates on what to do.


	6. Chapter 6

Asta debated with himself on what to do unaware the devil inside him had noticed Yami's darkness magic interferes with the other word. The devil wanted to feed on Yami's mana.

Yami laid in his bed relaxing. He was ready for a good nap. But first he needed a good buzz to sleep off. Yami gets himself a mug of beer and sets to drinking.

Asta shakes the thoughts from his head and he goes to take a nap. But the dream turns into a nightmare. Yuno was the Wizard King and the black bulls were no more as the Clover Kingdom didn't want magic Knights whose captain couldn't keep his pants dry. Asta tosses and turns as he tries to fight off the nightmare.

The devil doesn't let up. It had to feed off Yamis dark mana. Asta since he had no magic couldn't make the devil stronger. No the devil inside Asta felt Yamis mana when he lent Asta more power to fight back.

Asta couldn't take it anymore they would laugh they would. He couldn't let Yuno be the Wizard King he couldn't.

Yami taicho isn't gonna like this but it's the right thing to do." Asta reasons.

The demon smiles. Yami was in his room he had drank a whole barrel of booze and was napping after his long day. 

Asta comes into the room and he was having second thoughts. The demon senses this and it curses Yamis bladder. It wasn't as strong as the demon queen of curses but the simple curse would suffice.

Yami starts wetting in his sleep. Asta didn't know the demon inside him was the cause of this. He was thinking his Taicho wasn't as grown as he thought he was.


	7. Chapter 7

Yami was sound asleep. Asta looks for the mat and is annoyed as he sees Yami had cut it to ribbons.

Asta shakes his head in disappointment at the ruined mat.

Yami turns over in his sleep. He was grumbling but still very much asleep. Asta rolls Yami onto his back and starts to remove Yamis wet pants

Asta hesitates for a bit seeing his Taicho in such a modest state but the fundoshi is soaked.

Asta removes the soaked fundoshi and he blushes as he sees Yamis cock. Even soft it was almost as big as Asta when he got really excited.

Asta looks for the knapsack he sees it in Yamis trash bin. He digs it out and gets the powder and gets the wipes and he starts cleaning Yamis crotch. 

Yami begins to stir as he felt someone on his cock. He didn't remember heading to a brothel but he must've. But Yami sober up quickly when his eyes comes into focus and he sees Asta.

"What the hell are you doing in here get out!" Yami yells angrily. Asta doesnt move an inch.

Get the hell out of my room now brat I'm not gonna tell you again!" Yami yells angrily.

Yami realizing he is naked grabs his sheets to cover himself.

"Yami Taicho I told you I'm gonna take care of everything." Asta replies soflty.

"Take care of the hell you talking about this is my room Asta you damn brat now go before I make you leave!" Yami warned Asta.

"Taicho you had another accident. I don't think it was an accident. Yami taicho you aren't a man." Asta says bluntly.

"Not a man? Asta you better turn right back around and get out of my room before I lose it" Yami says as he gives Asta a glare.

Taicho now you need to settle down. I'm helping you!" Asta yells back as he tries to get through to Yami

Yami wasn't having this and he wraps his sheet over him and he tells Asta one more time to get out of his room.

Asta doesn't listen and instead tells Yami "Taicho what will the kingdom think if you have an accident again huh I'm doing this for you and the Black bulls. Sister says men dont wet and they certainly don't mess themselves!"


	8. Chapter 8

The devil in Asta was feeding off the heated exchange. It needed Yami weaker. It needed the dark magic user more humiliated. 

"Asta you may have turned 18 but that doesn't make you a man you're just a boy with a big mouth. You have a ways to go if you want to be Wizard king now goodnight!" Yami says firmly.

"Taicho seriously men don't have accidents especially not during the day!" Asta argues. 

"You still going on about you hit my gut Asta I hadn't gone in days so it was an accident that's all."

"Oh yeah and is that an accident?" Asta says as he points to Yamis discarded soaked fundoshi and pants.

Yami sees the articles of clothing and he was at a lost for words. Surely he didn't piss himself not in his sleep no. Was it the alcohol he wondered. No that didn't make sense Yami would pass out sure but he'd never pissed himself in his sleep.

"Yami Taicho listen it'll pass I use to wet my bed when I was small and sister made me wear those and I stopped after a few days you'll see you'll be back to normal in not time." Asta says

I'm not wearing those Asta and this conversation is over!" Yami says as he gets up still covering himself with his sheet as he gets a change of clothes.

Asta says "Yami taicho it's just for tonight no one has to know. Won't it beat a wet bed and sheets after all the laundry room is past Magna senpais room he'll or someone else will spot you."

"Again Asta it was a freak accident I let my guard down nothing more. And speaking of rooms this isn't your room so I suggest you find yours!" Yami replies as he gets a new pair of pants on.


End file.
